河道堤防老化指标体系评定之浅见

水利工程老化、失修是当前工程不能发挥正常效益的主要原因,建立工程老化指标评价体系是解决该问题的基础工作之一。老化是工程建成后在自然因素和人为活动长期连续的作用下,工程效益衰减、构件功能降低及材料性能逐渐变坏的自然现象。河道堤防以土石为主要材料,应以工程的功能为主建立老化指标体系。依据对工程效益和安全的影响程度,水利工程的综合老化度可分为四级。工程损坏后,在防洪工程运用年度内未能修复称为水利工程失修。解决老化问题主要依靠折旧或大修费,而解决失修问题主要依靠运行管理和维修养护费。     

Volumetric three‐dimensional up‐conversion display medium

Abstract— Several rare‐earth‐doped fluoride crystals that are excited to emit visible light by sequential two‐photon absorption have been investigated as display‐medium candidates for static volumetric three‐dimensional displays. Dispersion of powders of these materials in a refractive‐index‐matched polymer is reported because such a medium may result in a scalable display. The scattering problem in such a medium is greatly reduced by index‐matching the polymer to the crystalline particles. An index‐matching condition that optimizes the performance is identified.     

Metaheuristic downhill simplex method in combinatorial optimization

The concept of combinatorial objects is formalized. It allows strict definition of a combinatorial optimization problem (COP). An efficient metaheuristic method to solve COPs (H-method) is considered. It includes stochastic local search algorithms as a built-in procedure. A parallel implementation of the H-method is set forth and analyzed. The results from a numerical experiment and solution of some well-known COPs on personal computers and on the SKIT cluster supercomputer are presented. The study was supported by INTAS (Project 06-1000017-8909). __________ Translated from Kibernetika i Sistemnyi Analiz, No. 6, pp. 70–79, November–December 2007.     

C pm MPPAC for manufacturing quality control applied to the precision voltage reference process

The multiprocess performance analysis chart (MPPAC) based on the process capability index C_pm, called C_pm MPPAC, is developed for analysing the manufacturing quality of a group of processes in a multiple process environment. The C_pm MPPAC conveys critical information of multiple processes regarding the departure of the process and process variability from one single chart. Existing research works on MPPAC are restricted to obtaining quality information from one single sample of each process ignoring sampling errors. The information provided from existing MPPAC charts, therefore, is unreliable and misleading and results in incorrect decisions. In this paper, we consider the natural estimator of C_pm based on multiple samples. Based on the natural estimator of C_pm, we consider the sampling errors by providing an explicit formula with the Matlab program to obtain the estimation accuracy of the C_pm. We tabulate the sampling accuracy of C_pm for sample size determination so that the engineers/practitioners can use it for their in-plant applications. An example of multiple precision voltage reference (PVR) processes is presented to illustrate the applicability of C_pm MPPAC for manufacturing quality control.     

用测井资料预测储层的润湿性

岩心电性及润湿性实验测量结果表明，润湿性对阿尔奇饱和度指数n有很大影响。通过引入相对润湿指数，发现阿尔奇饱和度指数n的对数与相润湿指数之间存在很好的线性关系，为利用饱和度指数预测储层的润湿性提供了依据。同时使用电磁波传播测井和微球形聚焦电阻率测井求出饱和度指数随地层深度的变化曲线，预测储层的润湿性。现场井资料处理结果表明，该方法能快速直观显示不同深度处储层润湿性的变化。     

一种测定深部岩体地应力的新方法——钻孔局部壁面应力全解除法

简要回顾了基于钻孔进行地应力测量的几种方法，并指出了这些方法自身存在的局限性。提出了一种测定深部岩体地应力的新方法-钻孔局部壁面应力全解除法。该方法的明显优点是，不需要套钻，而且在确定地应力的主值及其方向时也不需要作任何假定。从理论上讲，该方法将不受测量深度的限制，对于深钻孔是普遍适用的，这将为大陆科学钻探计划中深部岩体地应力测量提供一种新途径。     

基坑工程表观监测与安全预警问题的研究

该文阐述了基坑工程的基本特点及复杂性 ,介绍了基坑工程表观监测的基本方法及监测中的若干技术问题 ,提出了基坑工程安全预警的一些量化指标。     

低空大气对连续波干涉仪系统相位稳定性的影响

针对三站连续波干涉仪系统，根据实时测得的系统场区大气折射率漂移数据，应用几何光学方法，从理论上估计了连续波干波仪系统两条微波基线传输的相位稳定性。     

A robust watermarking algorithm based on QR factorization and DCT using quantization index modulation technique

We propose a robust digital watermarking algorithm for copyright protection.A stable feature is obtained by utilizing QR factorization and discrete cosine transform(DCT) techniques,and a meaningful watermark image is embedded into an image by modifying the stable feature with a quantization index modulation(QIM) method.The combination of QR factorization,DCT,and QIM techniques guarantees the robustness of the algorithm.Furthermore,an embedding location selection method is exploited to select blocks with small modifications as the embedding locations.This can minimize the embedding distortion and greatly improve the imperceptibility of our scheme.Several standard images were tested and the experimental results were compared with those of other published schemes.The results demonstrate that our proposed scheme can achieve not only better imperceptibility,but also stronger robustness against common signal processing operations and lossy compressions,such as filtering,noise addition,scaling,sharpening,rotation,cropping,and JPEG/JPEG2000 compression.     

全局优化的一类新的F-C函数

针对求解全局优化问题,有很多种求解方法。文中提出了一种快速求解一般无约束最优化问题的辅助函数方法。即F-C函数方法。该方法与填充函数法和跨越函数法相比较,既有相同点又有不同点。F-C函数法最大的优点就是在极小化F-C函数阶段中只需要进行一次局部极小化算法就能得到比当前极小值更低的目标函数局部极小点。文中在无Lipschitz连续的条件下,给出了一类新的求解全局优化问题的F-C函数。文中讨论了该F-C函数的优良性质并对该函数设计了相应的算法。最后,通过数值试验表明该F-C函数方法具有有效性和可行性。